Mexico City: The empty Basilica of Our Lady of Guadalupe during mass following the deadly swine flu outbreak. More than 500 cultural and athletic events have been cancelled by government order in the capital city alone

Denpasar, Bali, Indonesia: A health official monitors arriving passengers with thermal scanners at Ngurah Rai international airport. Indonesia increased surveillance at all entry points for travelers with flu-like symptoms using devices at airports that were put in place years ago to monitor for Sars and bird flu

Hong Kong, China: Health workers watch a bank of monitors which display information on the temperatures of incoming passengers at the international airport in Hong Kong - a city at the forefront of the Sars epidemic in 2003

Singapore: A health screening official checks a passenger for his temperature arriving at terminal three of Changi airport. In light of the outbreak of swine flu cases in Mexico and the US, all passengers arriving at Singapore's main Changi airport are being screened for flu symptoms

Almansa, Spain: A guard gestures to journalists outside the Hospital General in Almansa, where the only confirmed case of swine flu in Spain is hospitalised. Spain's Health Ministry confirmed Europe's first case of swine flu and said another 20 people are suspected of having the disease. Health Minister Trinidad Jiménez said the patient is a young man who had recently returned from Mexico where he had been as part of his university studies

Washington DC, US: Barack Obama addresses the National Academy of Sciences. The president said he was closely watching an outbreak of swine flu in the United States, where 20 cases have so far been identified, but urged people to remain calm, saying: 'This is obviously a cause for concern and requires a heightened state of alert, but it's not a cause for alarm'